The conditions include Noonan spectrum disorders (NSD), skeletal disorders, craniosynostosis syndromes, Cornelia de Lange syndrome (CdLS), Alagille syndrome, tuberous sclerosis, epileptic encephalopathy, SYNGAP1‐related intellectual disability, CHARGE syndrome, Sotos syndrome and Rett syndrome. The gene discussed is SYNGAP1; the disease is Alagille syndrome.